Surgical stapler with articulation locking mechanism

ABSTRACT

The present disclosure is directed to an endoscopic surgical stapler having an articulation locking mechanism that functions to prevent straightening of a tool assembly of the surgical stapler when the surgical stapler is fired with the tool assembly in an articulated position. In embodiments, a mounting assembly supports a notched member on a proximal end of the tool assembly and the notched member defines a series of notches. An articulation member supported adjacent to the mounting assembly includes a locking member defining protrusions or teeth that are movable from a first unlocked position spaced from the notches of the mounting assembly to a second locked position received within the notches to lock the tool assembly in one of a plurality of articulated positions. In embodiments, the locking member is biased towards the unlocked position by a biasing member and is urged toward and retained in the locked position via engagement with a drive assembly of the surgical stapler.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical staplers and, more particularly, to endoscopic surgical staplers including articulating tool assemblies.

2. Background of Related Art

Surgical staplers configured for insertion through small incisions in the skin and/or through cannulas placed through small incisions in the skin are well known in the medical arts. Such staplers, referred to generally herein as endoscopic staplers, are used during endoscopic surgical procedures to minimize patient trauma and reduce patient recovery time as compared to traditional open surgical staplers.

Known endoscopic surgical staplers include tool assemblies that can be manipulated, e.g., rotated, articulated, etc., via a hand piece to facilitate easier access to tissue within a patient. In conventional surgical staplers having articulable tool assemblies, it is difficult to retain the tool assembly at a desired degree of articulation during firing of the surgical stapler because the firing forces operate to straighten the tool assembly. Accordingly, a continuing need exists in the medical arts for an articulable surgical stapler that is better able to retain a desired degree of articulation during firing of the surgical stapler.

SUMMARY

In accordance with aspects of the present disclosure, a surgical stapler is provided including an actuating device having a firing trigger and an articulation lever, an elongated body defining a longitudinal axis and extending distally from the actuating device, and a tool assembly supported on the elongated body. The tool assembly is supported for articulation about an axis transverse to the longitudinal axis in response to actuation of the articulation lever. A drive assembly is supported within the elongated body and is movable between a retracted position and an advanced position to actuate the tool assembly. An articulation locking mechanism is supported on the distal end of the elongated body and includes a locking member. In response to movement of the drive assembly from the retracted position towards the advanced position, the locking member is movable from an unlocked position disengaged from the tool assembly to a locked position engaged with the tool assembly to prevent further articulation of the tool assembly.

In embodiments, the articulation member includes a biasing member positioned to urge the locking member towards the unlocked position.

In some embodiments, the tool assembly includes a cartridge assembly and an anvil assembly.

In certain embodiments, the surgical stapler further includes a mounting assembly supported on the proximal end of the tool assembly, and the anvil and cartridge assemblies are pivotally supported on the mounting assembly in relation to each other for pivoting between open and clamped positions.

In embodiments, the mounting assembly defines notches and the locking member defines teeth, and the teeth are received within the notches in the locked position.

In some embodiments, the drive assembly includes a drive bar having an upper surface defining a recess, and the locking member is positioned within the recess when the drive assembly is in the retracted position.

In certain embodiments, the surgical stapler further includes a biasing member positioned to urge the locking member to the unlocked position.

In embodiments, the locking member includes an abutment and the drive bar defines a cam surface, the cam surface being positioned to engage the abutment when the drive assembly is moved from the retracted position towards the advanced position, and to move the locking member from the unlocked position to the locked position.

In certain embodiments, a distal portion of the elongated body and the tool assembly form a reload assembly that is releasably coupled to a proximal portion of the elongated body.

In embodiments, the firing trigger of the actuating device is manually driven.

In some embodiments, the hand piece is electrically powered.

In certain embodiments, the hand piece supports a rotation knob that is rotatable in relation to the hand piece to effect rotation of the elongated body and the tool assembly in relation to the hand piece.

In accordance with other aspects of the present disclosure, a surgical stapler includes an elongated body defining a longitudinal axis and a tool assembly supported on the elongated body. The tool assembly is supported for articulation about an axis transverse to the longitudinal axis in response to actuation of the articulation lever. A drive assembly is supported within the elongated body and is movable between a retracted position and an advanced position to actuate the tool assembly. An articulation locking mechanism is supported on the distal end of the elongated body and includes a locking member. In response to movement of the drive assembly from the retracted position towards the advanced position, the locking member is movable from an unlocked position disengaged from the tool assembly to a locked position engaged with the tool assembly to prevent further articulation of the tool assembly.

In embodiments, the tool assembly includes a cartridge assembly and an anvil assembly.

In some embodiments, the surgical stapler includes a mounting assembly supported on the proximal end of the tool assembly, and the anvil and cartridge assemblies are pivotally supported on the mounting assembly in relation to each other for pivoting between open and clamped positions.

In certain embodiments, the mounting assembly defines notches and the locking member defines teeth, and the teeth are received within the notches in the locked position.

In embodiments, the drive assembly includes a drive bar having an upper surface defining a recess, and the locking member is positioned within the recess when the drive assembly is in the retracted position.

In some embodiments, the surgical stapler further includes a biasing member positioned to urge the locking member to the unlocked position.

In certain embodiments, the locking member includes an abutment and the drive bar defines a cam surface, the cam surface being positioned to engage the abutment when the drive assembly is moved from the retracted position towards the advanced position, and to move the locking member from the unlocked position to the locked position.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the presently disclosed endoscopic surgical stapler are described herein with reference to the drawings, wherein:

FIG. 1 is a side perspective view of a surgical stapler in accordance with the present disclosure with a tool assembly in a non-articulated, open position;

FIG. 2 is a side view of a distal end of the body and the tool assembly of the surgical stapler shown in FIG. 1 in an articulated, open position;

FIG. 3 is a side, perspective view of the distal end of the body and the tool assembly of the surgical stapler shown in FIG. 2 with parts separated;

FIG. 4 is an enlarged view of the indicated area of detail shown in FIG. 3;

FIG. 5 is a bottom, perspective view of an upper mounting portion of a mounting assembly of the tool assembly of the surgical stapler shown in FIG. 3;

FIG. 6 is top view of the distal end of the body and the tool assembly of the surgical stapler shown in FIG. 1 in the non-articulated position with an upper section of the body removed and the anvil and cartridge assemblies shown in phantom;

FIG. 7 is a side perspective view of the mounting assembly of the tool assembly shown in FIG. 1, and the distal end of the body and drive assembly of the surgical stapler shown in FIG. 1, with the upper section of the body removed, the drive assembly in a retracted position, the mounting assembly in a non-articulated position, and an articulation locking mechanism in the unlocked position;

FIG. 8 is a cross-sectional view taken along section line 8-8 of FIG. 7;

FIG. 9 is a side perspective view of the mounting assembly of the tool assembly shown in FIG. 1 and the distal end of the body and drive assembly of the surgical stapler shown in FIG. 1, with the upper section of the body removed, the drive assembly in a retracted position, the mounting assembly in an articulated position, and the articulation locking mechanism in the unlocked position;

FIG. 10 is a side perspective view of the mounting assembly of the tool assembly shown in FIG. 1 and the distal end of the body and drive assembly of the surgical stapler shown in FIG. 1, with the upper section of the body removed, the drive assembly in a partially advanced position, the mounting assembly in a non-articulated position, and the articulation locking mechanism in the locked position;

FIG. 11 is top view of the distal end of the body and the tool assembly of the surgical stapler shown in FIG. 1 in the articulated position with an upper section of the body removed and the anvil and cartridge assemblies shown in phantom;

FIG. 12 is a side perspective view of the mounting assembly of the tool assembly shown in FIG. 1 and the distal end of the body and drive assembly of the surgical stapler shown in FIG. 1, with the upper section of the body removed, the drive assembly in a partially advanced position, the mounting assembly in an articulated position, and the articulation locking mechanism in the locked position; and

FIG. 13 is a side cross-sectional view taken along section line 13-13 of FIG. 10.

DETAILED DESCRIPTION OF EMBODIMENTS

The present disclosure is directed to an endoscopic surgical stapler having an articulation locking mechanism that functions to prevent straightening of a tool assembly of the surgical stapler when the surgical stapler is fired. The presently disclosed surgical stapler includes a mounting assembly the supports a notched member on a proximal end of the tool assembly. The notched member defines a series of notches. The surgical stapler also includes a body having a distal end that supports the articulation locking mechanism adjacent the notched member. The articulation member includes a locking member defining protrusions or teeth that are movable from a first unlocked position spaced from the notches to a second locked position received within the notches to lock the tool assembly in one of a plurality of articulated positions as described in further detail below. In embodiments, the locking member is biased towards the unlocked position by a biasing member and is urged toward and retained in the locked position via engagement with a drive assembly of the surgical stapler.

Embodiments of the presently disclosed surgical stapler with articulation locking mechanism will now be described in detail with reference to the drawings wherein like reference numerals designate identical or corresponding elements in each of the several views. In this description, the term “proximal” is used generally to refer to the portion of the stapler that is closer to a clinician, while the term “distal” is used generally to refer to the portion of the stapler that is farther from the clinician. In addition, the term “endoscopic” procedure is used generally to refer to endoscopic, laparoscopic, arthroscopic, and any other surgical procedure performed through a small incision or a cannula inserted into a patient's body. Finally, the term clinician is used generally to refer to medical personnel including doctors, nurses, and support personnel.

Referring to FIGS. 1 and 2, the presently disclosed surgical stapler 10 includes an actuating device or handle assembly 12, an elongated body 14 and a tool assembly 16. The tool assembly 16 may form part of a reload assembly 18 having a proximal body portion 18 a which is releasably connected to the elongated body 14. The proximal body portion 18 a forms a distal end of the elongated body 14. Alternatively, the tool assembly 16 may be directly connected to the distal end of the elongated body 14. The actuating device 12, although shown as manually driven, may be in the form of an electrically powered hand piece (not shown) that is connected to the tool assembly 16 by an adapter (not shown). U.S. Publication No. 2015/0157320 discloses embodiments of a powered hand piece and adapter and is incorporated herein by reference in its entirety.

Surgical stapler 10 includes a rotation knob 20 that supports an articulation lever 22. The rotation knob 20 is supported for rotation on the handle assembly 12 to effect rotation of the elongated body 14 and the tool assembly 16 in relation to the handle assembly 12. The articulation lever 22 is actuable to articulate the tool assembly 16 about an axis transverse to a longitudinal axis of the elongated body 14. The handle assembly 12 also includes a firing trigger 24 and a retraction knob 26. U.S. Pat. No. 8,292,152 ('152 Patent) discloses a surgical stapler including embodiments of the presently disclosed handle assembly 12 and is incorporated herein by reference in its entirety.

Referring also to FIG. 3, the tool assembly 16 includes an anvil assembly 30 and a cartridge assembly 32. The anvil assembly 30 has a distal portion defining a tissue engaging surface 34 and a proximal end adapted to receive a mounting assembly 36 as described in further detail below. As is known in the art, the tissue engaging surface 34 defines staple deforming pockets (not shown). The proximal end of the anvil assembly 30 supports a proximally extending flange 38 defining a through bore 40. The proximal end of the anvil assembly 30 also includes a pair of spaced downwardly extending legs 42 (only one is shown) that define a cavity 44 that is configured to receive a portion of the mounting assembly 36. Each of the legs 42 defines a through bore 46 that is dimensioned to receive a pin 48 to secure the anvil assembly 30 to the mounting assembly 36 as described in further detail below.

The cartridge assembly 32 includes a channel 50 that defines a cavity that receives a staple cartridge 52. The staple cartridge 52 is similar to the staple cartridge described in the '152 Patent and will not be described in further detail below. A proximal end of the channel 50 defines spaced sidewalls 54 that are received between the legs 42 of the anvil assembly 30. Each of the sidewalls 54 defines a through bore 56 that is aligned with a respective through bore 46 of the anvil assembly 30 and receives one of the pins 48 to pivotally secure the cartridge assembly 32 adjacent to the anvil assembly 30.

The mounting assembly 36 includes an upper mounting portion 60 and a lower mounting portion 62. The lower mounting portion 62 includes a pair of extensions 64 that are positioned between the sidewalls 54 of the channel 50 of the cartridge assembly 32. Each of the extensions 64 defines a bore 66 that receives a respective one of pins 48 to secure the lower mounting portion 62 to the proximal end of the tool assembly 16. The upper mounting portion 60 is secured atop the lower mounting portion 62 by pins or rivets 70. Each of the upper and lower mounting portions 60 and 62 includes a circular protrusion 72 (only the upper protrusion is shown) which defines a pivot axis for the tool assembly 16 that is transverse to the longitudinal axis of the elongated body 14.

The distal end of the elongated body 14 of the surgical stapler 10 (or the proximal end of the reload assembly 18) includes an upper body portion 74 and a lower body portion 76. Each of the upper and lower body portions 74 and 76 defines a stepped recess 80. The stepped recess 80 receives a stepped coupling member 82 to fixedly retain the coupling member 80 in relation to the upper and lower body portions 74 and 76. Each of the coupling members 82 defines a through bore 84 that receives the circular protrusion 72 of one of the upper and lower mounting portions 60 and 62 to secure the tool assembly 16 for rotation in relation to the distal end of the elongated body 14.

A drive assembly 90 is movable within the distal end of the elongated body 14 between retracted and advanced positions. The drive assembly 90 includes a resilient drive bar 92 and a dynamic clamping member 94 that supports a knife blade 94 a. The dynamic clamping member 92 is positioned adjacent a proximal end of the tool assembly 16 when the drive assembly 90 is in its retracted position. When the drive assembly 90 is moved from its retracted position towards its advanced position, the dynamic clamping member 92 moves through the tool assembly 16 to pivot the cartridge assembly 32 in relation to the anvil assembly 30 from an open position to a clamped position and to subsequently fire staples from the staple cartridge 52. The '152 Patent discloses a similar drive assembly 90 and its method of operation as it moves the tool assembly from the open position to the clamped position and fires staples from the staple cartridge.

The surgical stapler 10 includes an articulation rod 98 having a distal end that is secured to the upper mounting portion 60 by one of the pins 70 at a location offset from the pivot axis defined by the protrusion 72 on the upper mounting portion 60. The proximal end of the articulation rod 98 is operatively connected to the articulation lever 22 (FIG. 1) such that when the articulation rod 98 is advanced and retracted within the elongated body 14, the tool assembly 16 is pivoted about the pivot axis defined by the protrusion 72. Further details of the interconnection of the articulation rod 98 and the articulation lever 22 are provided in the '152 Patent.

The drive bar 92 of the presently disclosed drive assembly 90 is resilient and includes an upper surface 92 a defining a recess 96. The recess 96 is positioned beneath the coupling member 82 of the upper body portion 74.

Referring to FIGS. 3-5, an articulation locking mechanism 100 is positioned within a recess 101 that communicates with the stepped recess 80 formed in the upper body portion 74. The articulation locking mechanism 100 is positioned between the coupling member 82 of the upper mounting portion 60 and the upper surface 92 a of the drive bar 92 of the drive assembly 90 and includes a locking member 102 and a biasing member 104. The biasing member 104, which may be in the form of a V-shaped compression spring, is positioned between the coupling member 82 and the locking member 102 to urge the locking member 102 towards the upper surface 92 a of the drive bar 92 into the recess 96 (FIG. 3) as described in further detail below. Alternatively, other biasing member types may be used to urge the locking member 102 towards the upper surface 92 a of the drive bar 92. In embodiments, the biasing member 104 may be fixedly secured to the locking member 102 or positioned atop the locking member 102.

The locking member 102 includes a distal end defining a plurality of spaced teeth 106 and a proximal end defining a flange 108. In embodiments, the flange 108 extends upwardly towards the coupling member 80 and defines guide recess 112 that receives the coupling member 80 (FIG. 3).

The upper mounting portion 60 (FIG. 5) includes a curved proximal end 114 that defines a plurality of notches 116 (FIG. 5) positioned in alignment with the teeth 106 of the locking member 102. When the locking member 102 is in a lowered or unlocked position within the recess 96 of the drive bar 92, the teeth 106 of the locking member 102 are positioned beneath the notches 116 of the upper mounting portion 60 and the tool assembly 16 is free to articulate about the pivot axis defined by the protrusion 72 (FIG. 3). When the locking member 102 is moved from within the recess 96 to a raised position as described in detail below, the teeth 106 of the locking member 102 are received within the notches 116 of the upper mounting portion 60 to rotatably fix the tool assembly 16 in relation to the elongated body 14 in any one of a plurality of articulated positions.

Referring to FIGS. 6-9, when the drive assembly 90 is in a retracted position, the biasing member 104 of the articulation locking member 100 urges the locking member 102 in the direction indicated by arrow “A” in FIG. 8 to a position at least partially within the recess 96 of the drive bar 92 of the drive assembly 90. In this position, the articulation rod 98 (FIG. 6) of the surgical stapler 10 is linearly movable via actuation of the articulation lever 22 (FIG. 1) to articulate the tool assembly 16 in relation to the elongated body 14 (FIG. 9).

Referring to FIGS. 10-13, when the drive assembly 90 is advanced from a retracted position (FIG. 6) towards an advanced position to move the tool assembly 16 from an open position to a clamped position and subsequently fire staples from the staple cartridge 52 (FIG. 3), the distal end of the drive bar 92 moves distally within the elongated body 14 (FIG. 1) and into the tool assembly 16 (FIG. 11) to move the recess 96 (FIG. 13) in the direction indicated by arrow “B” in FIG. 13 from beneath locking member 102. As the drive bar 92 moves distally, a cam surface 117 defined by the drive bar 92 adjacent a proximal end of the recess 96 engages an abutment 118 formed on a bottom surface 120 of the locking member 102. When the cam surface 117 engages the abutment 118 of the locking member 102, the locking member 102 is urged upwardly in the direction of arrow “C” in FIG. 13 against the bias of biasing member 104 to the raised position. In the raised position, the spaced teeth 106 of the locking member 102 are received within the notches 116 to rotatably fix the tool assembly 16 in relation to the elongated body 14 of the surgical stapler 10 in one of a plurality of articulated positions. More specifically, because the locking member 102 is fixedly positioned within the recess 101 formed in the upper body portion 74 of the elongated body 14, when the teeth 106 of locking member 102 are received within the notches 116 of the upper mounting portion 60, further articulation of the tool assembly 16 is prevented. Although not shown, the tool assembly 16 may be mounted for articulation over a range of angles between 90° and 180°. As such, the notches 116 of the upper mounting portion 60 can extend over an arc of between 90° and 180°.

As shown in FIGS. 11-13, when the drive assembly 90 is advanced from the retracted position towards the advanced position with the tool assembly 16 in an articulated position, the cam surface 117 (FIG. 13) on the upper surface 92 a of the drive bar 92 urges the locking member 102 upwardly to position teeth 106 within the notches 116 of the upper mounting portion 60. By positioning teeth 106 within the notches 116, the mounting assembly 36 is prevented from rotating, i.e., articulating, in relation to the locking member 102 and the elongated body 14. Thus, the locking member 102 counteracts the force of the drive assembly 90 that tends to straighten the articulated tool assembly 16 during firing of the surgical stapler 10 to retain the tool assembly 16 in a fixed articulated position.

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments. It is envisioned that the elements and features illustrated or described in connection with one exemplary embodiment may be combined with the elements and features of another without departing from the scope of the present disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described embodiments. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. 

What is claimed is:
 1. A surgical stapler comprising: an actuating device including a firing trigger and an articulation lever; an elongated body defining a longitudinal axis and extending distally from the actuating device; a tool assembly supported on the elongated body for articulation about an axis transverse to the longitudinal axis in response to actuation of the articulation lever; a drive assembly supported within the elongated body, the drive assembly being movable between a retracted position and an advanced position to actuate the tool assembly; and an articulation locking mechanism supported on the distal end of the elongated body, the articulation locking mechanism including a locking member that is movable in response to movement of the drive assembly from the retracted position towards the advanced position from an unlocked position disengaged from the tool assembly to a locked position engaged with the tool assembly to prevent further articulation of the tool assembly, wherein the drive assembly includes a drive bar having an upper surface defining a recess, the locking member being positioned within the recess when the drive assembly is in the retracted position.
 2. The surgical stapler according to claim 1, further including a biasing member positioned to urge the locking member to the unlocked position.
 3. The surgical stapler according to claim 2, wherein the locking member includes an abutment and the drive bar defines a cam surface, the cam surface being positioned to engage the abutment when the drive assembly is moved from the retracted position towards the advanced position to move the locking member from the unlocked position to the locked position.
 4. A surgical stapler comprising: an elongated body defining a longitudinal axis; a tool assembly supported on the elongated body, the tool assembly being articulable about an axis transverse to the longitudinal axis; a drive assembly movable from a retracted position towards an advanced position to actuate the tool assembly; and an articulation locking mechanism supported on the distal end of the elongated body, the articulation locking mechanism including a locking member that is movable from an unlocked position disengaged from the tool assembly to a locked position engaged with the tool assembly to prevent further articulation of the tool assembly in response to movement of the drive assembly from the retracted position towards the advanced position, wherein the drive assembly includes a drive bar having an upper surface defining a recess, the locking member being positioned within the recess when the drive assembly is in the retracted position.
 5. The surgical stapler according to claim 4, further including a biasing member positioned to urge the locking member to the unlocked position.
 6. The surgical stapler according to claim 5, wherein the locking member includes an abutment and the drive bar defines a cam surface, the cam surface being positioned to engage the abutment when the drive assembly is moved from the retracted position towards the advanced position to move the locking member from the unlocked position to the locked position. 